Buy on Amazon : http://www.amazon.com/gp/product/B005A1ZKN6?tag=catfoodrevi0a-20

Weatherproof WIRELESS HOME VIDEO SURVEILLANCE 4 CAMERA SYSTEM DVR

4 channels available at the same time
Built-in 12 IR LED for 7m night vision range
280TV line horizontal definition
Built-in microphone in camera enables audio monitoring
100m transmission distance without blockProfessional waterproof design enables work outside